daemon should reopen logfile on SIGHUP

[bugmenot]

After switching log file to a new one, compressing it, etc. tools like logrotate, newsyslog need for daemon to reopen the file, so they send SIGHUP by default. This can be worked around by using syslog.

[jordan]

There's a plausible use case for this feature, but it's not one that will affect very many people IMO.

This probably isn't going to be added unless someone submits a patch.

[gvdl]

Fixed waiting for commit

Note: #4895 SIGHUP race must be applied before this patch.

[gvdl]

Fixed patch to live onto of modified #4895.

[jordan]

• Probably shouldn't use optarg in gotsig()'s error message

• It would be better to key fropen off of logfileName instead of logfile -- it handles the stderr case automatically, and if a freopen fails, the next SIGHUP will still try to reopen.

• The "NULL != foo" is reasonable for avoiding accidental assigns, but I really don't like it. Instead of using "foo != NULL", I've split the difference and used "foo" here to avoid both accidental assigns and the non-lvalue-first idiom. :)

[jordan]

gvdl, any thoughts with recycle-logs.3.patch?

[gvdl]

Replying to jordan:

gvdl, any thoughts with recycle-logs.3.patch?

Sorry, I've been changing over my development system and getting a DS1512 setup as a Linux machine. That has distracted me. I'll try to look at it tonight.

[gvdl]

Reviewed recycle-logs.3.patch : No problems with me. BTW I agree with the NULL != idiom is horrible, It seemed that Roman coding (when in Rome...) required some sort of NULL comparison, I personally loath NULL comparisons. I've seen too many things go wrong with =/== and avoid them when comparing anything against zero.

I'm trying to work out how I got my patch to even compile and let alone run. There was no optarg parameter for the stderr printf in gotsig() weird as I really did test it believe it or not ;-). Anyway your patch is fine.

[cfpp2p]

I'm trying to work out how I got my patch to even compile and let alone run. There was no optarg parameter for the stderr printf in gotsig() weird as I really did test it believe it or not ;-). Anyway your patch is fine.

gotsig() is only called from main() where optarg parameter was defined, so that's why it compiled and ran OK.

[jordan]

Landed in r13330